Reversible neuropathy after chemotherapy for metastatic adenocarcinoma from an unknown primary tumor to the sural nerve.

Adenocarcinomas and other various tumors are known to metastasize to various locations without any significant predilection and the metastasis could be the first presentation of the malignancy by the patient. Involvement of peripheral nerves without the central nervous system involvement has been rarely reported. Perineural tumor spread has been infrequently reported with soft tissue tumors without central nervous system involvement. Here we present an unusual case of an elderly gentleman presenting with symptoms consistent with peripheral neuropathy involving multiple nerves. After failure of symptomatic therapy, electromyogram, and nerve conduction study showed severe bilateral carpal tunnel syndrome. Interestingly, symptoms worsened in the left hand after bilateral release surgery. Due to persistence of significant lifestyle-limiting symptoms, biopsy of the sural nerve was done that showed metastatic poorly differentiated adenocarcinoma cells. A complete surveillance for the primary lesion has been negative so far. The peripheral neuropathy was considered to be arising from the involvement of the perineural sheaths by the metastatic tumor lesions. The patient was then started on gemcitabine therapy and after just 2 cycles of chemotherapy, the patient has shown notable improvement of his symptoms. After completion of the duration of chemotherapy, he has been symptom-free for more than 6 months. Metastatic lesions to the peripheral nervous system should be considered in patients who have persisting neuropathic symptoms because treatment of those lesions can results in improvement of symptoms.

Hand-foot hyperpigmentation skin lesions associated with combination gemcitabine-carboplatin (GemCarbo) therapy.

Gemcitabine (Gemzar) is a nucleoside analogue used as a cytotoxic agent for the treatment of various carcinomas: pancreatic cancer, bladder cancer, breast cancer, and non-small-cell-lung cancer. Carboplatin, a DNA alkylating agent, is used alongside with gemcitabine in a regimen known as GemCarbo chemotherapy to treat several different types of cancer, most commonly lung cancer. We report an unusual case of hand-foot hyperpigmentation after the use of GemCarbo therapy on a man with stage IV non-small cell lung carcinoma. Physical examination revealed hyperpigmented lesions that were approximately 1-2 mm in diameter, of brown/purple discoloration localized to the palmar surface of his hands and the dorsum of his feet. A rapid plasma reagin blood test, used for the screening of syphilis was nonreactive. Discontinuation of both agents resulted in the dramatic disappearance of the lesions over the course of 2 weeks. In this report, we describe, to our knowledge, the first case of hand-foot hyperpigmentation that has been reported with the use of either of these 2 agents.